The use of superabsorbents in absorbent articles permits a substantial reduction in the bulk of the absorbent article. However, attempts to utilize superabsorbent materials in absorbent structures such as diapers and sanitary napkins have met with limited success. It is often difficult to "fix in place" or secure superabsorbents within the absorbent article. U.S. Pat. No. 3,971,379 discloses absorbent articles wherein a layer of superabsorbent is folded or rolled with another absorbent component of the absorbent article. Secondly, superabsorbent materials absorb and retain hundreds of times their weight of fluids, but they do not easily wick fluids. In an absorbent article, rapid swelling of the superabsorbent together with its lack of wicking ability can create a fluid "block", preventing the utilization of the remainder of the superabsorbent, or other absorbent materials in the absorbent article.
New methods of utilizing superabsorbents into absorbent articles focus on methods of incorporating the superabsorbent into a fibrous structure so as to avoid the blocking problem. U.S. Pat. No. 4,105,033 discloses a method of incorporating a superabsorbent into a fibrous structure, and U.S. Pat. No. 4,226,237 discloses a more elaborate fibrous structure of absorbent fibers and peat moss, into which superabsorbent may be distributed.
The present invention involves a new approach to the use of superabsorbents in an absorbent article. Rather than attempt to create new fibrous structures wherein the superabsorbent is so dispersed as to prevent blocking, the present invention may use known fibrous materials containing superabsorbents which materials when used alone may block. In the absorbent article of the present invention, the superabsorbent may be dispersed within a fibrous structure or cellular foam or may be present in a film, alone or together with other ingredients. According to the present invention, an internal wicking means is provided within the absorbent article to bring the fluid to the superabsorbent. The wicking means is wrapped or folded about discrete layers containing the superabsorbent.
Methods of folding absorbent fibrous materials to form absorbent articles are shown in U.S. Pat. No. 2,952,259. However, there is no teaching of superabsorbents or internal wicking means.